


Late Night

by Bone Δaddy (NadaCitizen)



Series: Involving Sans [2]
Category: Undertale, Undertale (Video Game)
Genre: Also Sans gets loud, Fire, For shame, Grinding, In Public, M/M, NSFW, On the table booth too, Pain, Sub Sans, This is nasty I'm nasty you're nasty, Undertail, heat - Freeform, sort of
Language: English
Status: Completed
Published: 2015-10-30
Updated: 2015-10-30
Packaged: 2018-04-28 21:53:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,009
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5107037
Author URL: https://archiveofourown.org/users/NadaCitizen/pseuds/Bone%20%CE%94addy
Summary: <blockquote class="userstuff">
              <p>Sans usually spends late nights at Grillby's for jokes and a snack. Tonight's going to be a little different.</p>
            </blockquote>





	Late Night

**Author's Note:**

> Inspired by this headcanon: 
> 
> http://wires-and-sinflowers.tumblr.com/post/132002423353

1:35 a.m. If one couldn’t tell by sneaking quick peeks at Grillby’s watch every time he got close, then one could surely guess it was the dead of night by the near-emptiness of the bar and the unusually chilly silence of Snowdin outside.

Like many other nights, Sans came by to relax and converse with the stoic object-head who would occasionally entertain his jokes.

At least, that had been his intention.

Sans slumped forward on the bar stool, crossing one arm while he used the other to grab a fry drowning in ketchup. Knowing the building would close within the half-hour, he scanned the room to see who remained: himself, a sleeping greater dog, a grumpy tooth monster, and a nonchalant Grillby.

Sleep crept up on him, but he had to put it off. Too many times the bartender had to wake him up in the middle of the night when he just needed to lock up the building. Not that it *embarrassed* Sans or anything, but… You feel bad after a few times. Especially when he only stayed this late for Grillby’s company; something about the post-midnight scene got him to speak more than a handful of words at a time. If he was lucky, he made him laugh. And being a loitering nuisance felt counter-productive to that.

What felt like ten minutes passed, and Sans was back on the verge of lethargy. His eyes shot open when he heard a voice across the room.

“If you like—“ Sans looked up at Grillby’s voice. “You can stay over and we can mess around.”

Pause. Sans barely turned away, not sure if he heard that right. He then shifted the opposite way, catching the other’s eye, and realized he hadn’t misheard anything. “Uh…”

Suddenly he become hyper-aware of each second that passed. *Yes*, he thought, abso-fucking-lutely. But never would he have guessed he’d be the one to ask.

As soon as Grillby did the habitual push up of his glasses, Sans nodded, refusing to lose the opportunity. “Sure.”

And right on cue, Grillby’s boots slowly clack along the wood paneling to meet the other face-to-face. Sans raises a brow, eyes flickering back and forth only to realize the rest of the patrons left. Carefully, he meets the objecthead’s gaze behind his frames.

“You know,” he could hear the shy smile in his voice. When he slid the lenses again up again, Sans took note of the leather gloves. Those were new. “I wouldn’t have expected that from you.”

“Uh…” He avoided clasping a hand over his face in embarrassment, but struggled to get a good enough look to appreciate the man towering over him. “Same to you. Can I ask why…?”

Beads of sweat gathered at the sides of Sans’ skull, but he felt relief at the easy answer. “Well, you’re my favorite regular.”

At least until the other leaned forward, cupping Sans’ cheekbone *just* enough for an icy-blue blush to conjure up. Despite the glove, his hand was still warm to the touch against his cheekbone. “Heh. So, uh…”

The blush burned darker after realizing how many times filler words invaded his sentences. Gotta stop. “What are those for?”

“Hmm?” Grillby takes a moment before noting Sans’ eyes locking onto the gloves. “Oh. I didn’t want to take a chance burning you.”

The objecthead chuckles softly, and Sans can’t help but find him cuter by the moment. “I—,“ he forces himself not to throw in another ‘uh’, “think it’d be fine. I mean…that’s what “messing around” is about, right?”

Before he could notice Grillby’s face burning a little warmer, Sans reached out and took it in both of his hands, only to immediately back off in pain. *Holy shit*. Immediately Grillby turns his away, rubbing the back of his head with a sigh. “Maybe we shouldn’t–…”

Just as quickly, Sans returns, adjusting his grip and pressing his mandible against what he assumed to be Grillby’s general mouth area. Skeletons don’t have lips, and Sans isn’t entirely sure if Grillby even has a mouth, but hell, he was *not* about to fuck this up. He could feel his hands searing, but found the pain easier to deal with once he felt the objecthead’s hand gently grasp Sans’ wrist and lean into the gesture.

They hold each other a few more seconds before Sans breaks away again, resting his palms flat against the cool countertop. Blue blush covered the entirety of his face, and he wasn’t sure how much was from heat and how much was from just how *nice* that was.

Grillby seems to have felt something similar, as he angles his head down shyly. After a moment, he slides his frames higher and attempts to lean in towards Sans, who accepts. They try again, but Sans struggles to hold it under the rising heat from Grillby’s blushing; he set his gloved hands on the skeleton’s forearms, shutting his eyes as he pressed his face forward.

Meanwhile, Sans hands shook, feeling as though his skull may *actually* melt off—but he pushed himself toward him anyway, beads of sweat roll down the back of his skull as his mouth parts to keep the other’s attention. It worked.

This time, Grillby stepped back, the general what-would-be cheek area of his face smoldering a richer red than the rest of it. Sans watched, raising his brows until he heard him speak.

“I…Hold on.”

So Sans did, taking the moment to look at himself in one of the freshly cleaned glasses sitting at the end of the bar. He touched his mouth and it appeared…mostly fine. But there was definitely some singing around the corners.

Soon enough, Grillby walked around the counter to meet Sans, the back of his heels clicking the entire way. Minus the foot-and-a-half of glossy bar between them, Sans felt an eagerness shoot through his spine. He *knew* it would hurt, but…

He took both of the objecthead’s hands and glued them to his sides, using the moment to pull him close. Bringing him *down* would have been a whole other level of difficult considering his height, but Grillby caught the hint and dipped his head to touch Sans’. Several minutes in, Grillby tightens his hold, now able to feel the other’s ribs—much to Sans’ chagrin, as a heavy sigh flow freely to accompany his flustered visage. “H—Hey, let’s try somewhere else. I’m not really feeling the countertop.”

Grillby sets an index finger on the bridge of his glasses, adjusting them while he glances around the room for an alternative. The booths seemed feasible, and Sans’ met his eye before striding straight there, leaving Grillby little room to argue.

He motioned for the bartender to slide in first, and Sans prepared to follow—but not without first pushing the table aside. Booths tended to be less forgiving to…big-boned monsters such as himself.

“All right, so…” Sans grinned, but genuinely thought it over: “Facts are facts. You’re pretty tall. You mind kind of…Lying down?”

Grillby froze for a second before complying, resting his elbows on the windowsill and letting a too-long leg dangle over the seat. Obviously, this was equally as knew to him—close contact was few and far between him and Snowdinians.

Nonetheless, Sans continued and shuffled on top of the other, straddling his lap and dropping his hands to his vest. Both paused, the air filled with a potpourri of embarrassment, excitement, and curiosity.

“…Thanks.” The skeleton breathed out, not expecting the other to agree so seamlessly. Grillby nodded, and Sans suddenly felt too warm. The coat had to go—so he shook his arms and wiggled out of it, tossing it onto the table.

The bartender clasped a hand over his jaw upon seeing Sans’ bare arms. Not so much because they were *arms*, but because he’d never seen Sans without it. A vibe of familiarity and provocation came with it.

“You okay, Grillby?” Sans grinned once he caught the other staring, and stretched it out wider after seeing him nod bashfully, but couldn’t help blushing himself when he felt the other grow *warmer* even through his clothes.

The objecthead noticed too; he loosened his bowtie, glancing away. Not one to pass up an opportunity, however, Sans dragged himself forward and grazed his fingertips along Grillby’s lower torso. “Heh…”

Not the best idea. Sans immediately felt straight fire underneath Grillby’s flameproof pants and winced, snatching the lower half of the other’s button-down. “A-hhh…”

Despite the pain, Sans refused to move from the seat. Something about it felt too good. After a brief judgement over the pros and cons of pushing it, Sans pursued, circling his pelvis around the entirety of Grillby’s hips, grinding roughly once the bartender started sighing aloud. *Hell yes*.

“Mmm…why don’t you…” Sans gasped, becoming overstimulated. “Take your gloves off…?”

Grillby furrows his brows, not sure. He looked down at them before Sans took one of his hands himself, biting the edge of one of the fingertips and tugging the glove off through his teeth. “You looked warm.”

He’d have rolled his eyes had Sans not proceeded to put his hand in his mouth, blushing crimson as he conjured a blue tongue to wrap around his fingers. “Mn…”

Sans held his breath as Grillby flared up once more, accidentally biting down on his fingers in the process—but the bartender didn’t seem to mind. Shaking his head, Sans switches his attention to Grillby’s lap again; this time, he casually began to unbutton and unzip, humming softly as the objecthead locked his knees. “Ah…”

And as soon as he pulled the pants down a few inches, Sans looked down, eyes widening as he brought a hand up to his own mouth. He’d never seen anything like it; a flame-consumed, ten-inch phallus stood tall where the zipper used to be, glowing hotly. Sans had to wipe saliva away from his mouth, blushing indigo. “Oh…”

As tempting as it was to just kind of admire it, impatience overtook him. Within moments, he’d already slid off his own basketball shorts and slid forward again, hovering over Grillby who just watched in shy curiosity.

Flustered but fearless, Sans made eye contact with Grillby as he lowered himself, making the both of them gasp simultaneously. “Nn…”

Soon Sans finds a rhythm, wiping away the sweat dotting at his forehead with an arm as he rocks himself forward and back, moaning softly at the simultaneously sweet and sadistic singeing. “Hah…”

Grillby bucked his hips often, especially as Sans picked up speed—he couldn’t help it; Sans’ bones were just so *cold*, a touch he literally couldn’t feel otherwise. Sans grinned every time, throwing his neck back and giving his tongue free reign to loll outside of his mouth.

At least, until Grillby really started heating up.

He couldn’t prepare for it, and only moaned out Sans’ name once he felt the pangs of arousal shoot through him; abruptly, straight flames danced underneath the skeleton, who dropped his jaw and arched his back on instinct.

*Holy fuck*.

Sans squirmed, moaning loudly as the delicious flames roared against his coccyx and his pubic symphysis, borderline yelling once the fire rose to brush against his spine. “A-aannhh…”

Grillby hooked his fiery hands onto Sans’ pelvis to hold him into place, softly groaning at every move the skeleton made.

“MM-MNNnnn…” The tongue Sans’ conjured dissipated; every ounce of energy he had left went straight to moaning, humping, and grabbing against the other, beginning to shake once embers brushed against his ribs. “H-hhhh…”

“Unghhh…” Little time needed to pass before Grillby climaxed, filling Sans’ ribcage with a magma-like ejaculate. The other could only shake, just collapsing and face-planting against the groove of the bartender’s shoulder, still moaning. “Nn…”

Grillby peeks at Sans, squinting as he realized his glasses flew off at some point. Oh well. He folded an arm over Sans’ lower back, absolutely drained.

Listening to the way Sans’ breathed now, heavy and desperate, Grillby decided next time, he would take his time.


End file.
